using System.Collections.Generic;
using System.Linq;
using Newtonsoft.Json;
using PetaPoco.Business;
using Sony.Filtr.Contracts.Definitions;
using Sony.Filtr.Contracts.Entities;
using Sony.Filtr.Core.LastModified;
using Sony.Filtr.DistributedCaching;

namespace Sony.Filtr.Core.ImageCarousel
{
    public class ImageCarouselManager
    {
        private readonly LastModifiedManager _lastModifiedManager;
        private readonly DistributedCacheHandler _distributedCacheHandler;

        public ImageCarouselManager(LastModifiedManager lastModifiedManager, DistributedCacheHandler distributedCacheHandler)
        {
            _lastModifiedManager = lastModifiedManager;
            _distributedCacheHandler = distributedCacheHandler;
        }

        public List<CarouselImage> GetImages(Application application)
        {
            List<CarouselImage> images = null;
            var cacheKey = GetImageCarouselCacheKey(application);
            var imageString = _distributedCacheHandler.Get(cacheKey) as string;
            if (imageString != null)
            {
                images = JsonConvert.DeserializeObject<List<CarouselImage>>(imageString);
            }
            
            if (images == null)
            {
                images = GetImagesInternal(application);
                _distributedCacheHandler.Put(cacheKey, JsonConvert.SerializeObject(images));
            }
            return images;
        }

        private static List<CarouselImage> GetImagesInternal(Application application)
        {
            if (application == null)
            {
                return PetaPocoRepository.Instance.Fetch<CarouselImage>();
            }

            return PetaPocoRepository.Instance.Fetch<CarouselImage>("WHERE applicationId=@0", application.ID);
        }

        public CarouselImage GetImage(int id)
        {
            return PetaPocoRepository.Instance.SingleOrDefault<CarouselImage>(id);
        }

        public CarouselImage SaveImage(CarouselImage image)
        {
            var savedImage = PetaPocoRepository.Instance.Upsert<CarouselImage>(image);
            _lastModifiedManager.SetLastModifyDate(image.ApplicationId, EntityType.CarouselImage);
            ClearCache(image);

            return savedImage;
        }

        public void DeleteImage(CarouselImage image)
        {
            PetaPocoRepository.Instance.Delete<CarouselImage>(image);
            _lastModifiedManager.SetLastModifyDate(image.ApplicationId, EntityType.CarouselImage);
            ClearCache(image);
        }

        private static string GetImageCarouselCacheKey(Application application)
        {
            var cacheKey = "ImageCarouselCacheKey-1.0:" + typeof(CarouselImage) + ":" + CarouselImage.Version + ":" + (application != null ? application.ID.ToString() : "null");
            return cacheKey;
        }

        private void ClearCache(CarouselImage carouselImage)
        {
            _distributedCacheHandler.Remove(GetImageCarouselCacheKey(new Application() { ID = carouselImage.ApplicationId }));
            _distributedCacheHandler.Remove(GetImageCarouselCacheKey(null));
        }

    }
}